Exhaust muffler



April 12, 1955 CARROLL 2,706,014

EXHAUST MUFFLER Filed Jan. 12, 1954 Fred H. Carroll I N V EN TOR.

United States Patent EXHAUST MUFFLER Fred H. Carroll, Jacksonville, Fla. Application January 12, 1954, Serial No. 403,570

3 Claims. (Cl. 181-53) This invention relates in general to improvements in exhaust mufilers, and more specifically to an exhaust muflier especially designed for use with internal combustion engines.

The primary object of this invention is to provide an improved exhaust mufiler which is relatively simple in construction and at the same time is so designed whereby it will remove a maximum amount of sound from exhaust gases.

Another object of this invention is to provide an improved exhaust muffler which is highly elfective in muffiing exhaust gases and at the same time, is relatively unrestricted whereby a back pressure in an exhaust pipe of an internal combustion engine is practically eliminated.

A further object of this invention is to provide an improved exhaust mufiler which is so efficient in operation and of such a nature whereby it may be conveniently attached to existing motor vehicles with a minimum of changes.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure l is a perspective view of the exhaust mufller which is the subject of this invention, end portions of inlet and outlet pipes being broken away;

Figure 2 is an enlarged fragmentary longitudinal sectional view taken substantially upon the plane indicated by the section line 22 of Figure 1 and shows the general construction of the exhaust mufiier;

Figure 3 is an enlarged transverse vertical sectional View taken substantially upon the plane indicated by the section line 3-3 of Figure 2 and shows the relationship of the casing with respect to a partition of the mufiler, also being shown is the relative shape of openings through the partition; and

Figure 4 is an enlarged transverse vertical sectional view taken substantially upon the plane indicated by the section line 44 of Figure 2 and shows the general relationship of the housing, the casing and outlet pipes of the exhaust muffier.

Referring now to the drawings in detail, it will be seen that there is illustrated the exhaust muffler which is the subect of this invention. The exhaust mufiier includes a housing which is referred to in general by the reference numeral 10. The housing is formed of an elongated cylindrical body member 12 which is closed at its opposite ends by end walls 14 and 16.

Disposed adjacent the end wall 16 and mounted within the housing 10 is a partition 18. The partition 18 is prefgrablly welded to the inner surface of the body mem- Also mounted within the housing 10 is a tubular casing which is referred to in general by the reference numeral 20. The tubular casing 20 has a cylindrical forward portion 22 whose forward end is secured to the inner surface of the wall 14. The casing 20 also includes a conical rear portion 24 which terminates at the partition 18. The smaller end of the conical rear portion 24 passes through an opening 26 in the partition 18 and is rigidly secured to the partition 18 by fastening means, such as welding 28.

It will be seen that the relationship of the housing 10, the casing 20 and the partition 18 is such that the exhaust muffier includes a plurality of chambers. For purposes of identification, the inner chamber within the casing 20 is referred to as a first chamber 30. A second chamber is disposed externally of the casing 20 and within the housing 10, the second chamber being referred to by the reference numeral 32. A third chamber 34 is disposed between the partition 18 and the end wall 16.

The exhaust mufiier also includes an inlet pipe 36 which passes through an opening 38 in the end wall 14 and ends within the first chamber 30. The inlet pipe 36 is rigidly secured to the end wall 14 by suitable fastening means, such as welding 40.

In order that exhaust gases may escape from within the housing 10, there is secured to the underside of the housing immediately adjacent the end wall 14 a curved forward portion 42 of a longitudinally extending outlet pipe 44. Also secured to the housing 10 just rearwardly of the connection of the curved portion 42 thereto is a curved portion 46 of a second outlet pipe 48. The outlet pipes 44 and 48 extend rearwardly in spaced parallel relation to the housing 10 and open to the atmosphere. The rear portions of the outlet pipes 44 and 48 are supported relative to the housing 10 by a clamp which is referred to in general by the reference numeral 50.

The clamp 50 includes first and second halves 52 and 54, respectively, which have upper portions 56 and 58, respectively, which are secured to the underside of the body portion 12 adjacent the partition 18. The lower ends of the halves 52 and 54 are connected together by a fastener 60 which is adjustable. The halves 52 and 54 are drawn together by the fastener 60 to tightly clamp the rear end portions of the outlet pipes 44 and 48.

In order that exhaust gases entering the first chamber 30 through the inlet pipe 36 may pass into the second chamber 32, the conical portion 24 of the casing 20 is provided with a plurality of perforations 62. Also, in order that exhaust gases may pass out of the third chamber 34 back into the second chamber 32, the partition 2; is provided with a pair of diametrically opposed slots In the normal operation of the exhaust mufiier which is the subject of this invention, exhaust gases direct from an internal combustion engine move rearwardly through the inlet pipe 36 and enter the forward portion of the first chamber 30. The exhaust gases then continue to move rearwardly through the first chamber 30 and pass out through the smaller rear end of the conical portion 24 of the casing 20 into the third chamber 34. The exhaust gases then have their directions reversed and move forwardly out of the third chamber 34 into the second chamber 32 around the casing 20 through the slots 64 in the partition 18. The exhaust gases next move rearwardly and enter into the curved forward portions 42 and 46 of the outlet pipes 44 and 48, respectively. The exhaust gases are then exhausted into the atmosphere.

As pressure builds up within the housing 10, particularly due to an increase in speed of the associated internal combustion engine, gases are forced through the perforations 62 in the conical portion 24 and moved directly from the first chamber 30 into the second chamber 32. The gases passing through the perforations 62 join the gases passing through the slots 64 and are exhausted through the outlet pipes 44 and 48.

The first chamber 30 is also communicated with the second chamber 32 by an opening 66 in the forward part of the cylindrical portion 22 of the casing 20. It will be noted that the opening 66 is aligned with the entrance to the curved portion 42 of the outlet pipe 44. When a low pressure exists within the housing 10, the opening 66, which is a by-pass hole, directs the gases into the outlet pipe 44 only, thus temporarily reducing the monoxide gas expelled to the atmosphere.

From the foregoing, the construction and operation of the device will be readily understood and further explanation is believed to be unnecessary. However, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claims.

What is claimed as new is as follows:

1. An exhaust mufiler comprising a housing having spaced end walls, a perforated casing mounted within said housing, one end of said casing being secured to one of said end walls, a partition in said housing adjacent the other of said end walls, the other end of said casing being secured to said partition, said casing having a first chamber therein, a second chamber between said casing and said housing, and a third chamber between said partition and said other end wall, an inlet pipe through said one end wall communicated with said first chamber, outlet pipes carried by said housing communicated with said second chamber, said casing opening through said partition to communicate said first and third chambers, said partition having at least one opening communicating said second and third chambers.

2. An exhaust muffler comprising a housing having spaced end walls, a casing mounted within said housing, one end of said casing being secured to one of said end walls, a partition in said housing adjacent the other of said end walls, the other end of said casing being secured to said partition, said casing having a first chamber therein, a second chamber between said casing and said housing, and a third chamber between said partition and said other end wall, an inlet pipe through said one end wall communicated with said first chamber, outlet pipes carried by said housing communicated with said second chamber,

said casing opening through said partition to communicate said first and third chambers, said partition having at least one opening communicating said second and third chambers, an end portion of said casing adjacent said partition communicating said first and second chambers.

3. An exhaust mufiler comprising a housing having spaced end walls, a casing mounted within said housing, one end of said casing being secured to one of said end walls, a partition in said housing adjacent the other of said end walls, the other end of said casing being secured to said partition, said casing having a first chamber therein, a second chamber between said casing and said housing, and a third chamber between said partition and said other end wall, an inlet pipe through said one end wall communicated with said first chamber, outlet pipes carried by said housing communicated with said second chamber, said casing opening through said partition to communicate said first and third chambers, said partition having at least one opening communicating said second and third chambers, an end portion of said casing adjacent said partition communicating said first and second chambers, said end portion being generally conical and tapering towards said partition.

References Cited in the file of this patent UNITED STATES PATENTS 

